Electrical conductor stud and method of making the same



Inventor- Robert HLs Attorne Oct. 21, 1930. R. M. $PURCK ELECTRICAL CONDUCTOR STUD AND METHOD OF MAKING THE SAME Filed Jan. 9, 1930 Patented Get. 21, 1930 UNITED STATES PATENT OFFICE ROBERT M. SPURCK, F LLANERCH, PENNSYLVANIA, ASSIGNOB TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK ELECTRICAL CONDUCTOR STUD AND METHOD OF MAKING THE SAME Application filed January 9, 1930. Serial No. 419,654.

My invention relates to electrical conductor studs and a method of making the same, and more particularly to conductor studs associated with electrical switch contact structure.

It is an object of my invention to provide an improved electrical conductor stud which shall be rugged and simple in construction, and have comparatively low efl'ective electrical resistance to alternating currents.

It is a further object of. my invention to provide a combined conductor stud and electrical switch contact so constructed as to substantially reduce the heat generated by ourrent traversing the conductor stud and contact.

My invention will be more fully set forth in the following description referring to the accompanying drawing, and the features of be pointed out with particularity in the claims annexed to and forming a part of this specification.

Referring to the drawing, Fig. 1 illustrates an elevational view, partly in section, of a conductor stud embodying my invention, and

Fig. 2 is a cross-sectional view taken along the line 22 of Fig. 1. In Fig. 1 of the drawing, there is illustfi trated by way of example, a conductor stud embodying my invention associated with switch contact structure. The conductor stud proper comprises a plurality of stranded copper conductors 1, arranged as in a bundle or cable and transposed so that the reactance of each individual circuit is approximately equal. As better illustrated in Fig. 2, each individual conductor is triangular in crosssection so as to form a sector of the cross 40 section of the entire stud. It shall be understood, however, that the form of cross section of the individual conductors is immaterial and that a com aratively large number of conductors each aving comparatively small cross section may be employed instead. Each conductor ispreferably insulated from the adjacent conductors by a suitable insulating coating, such for example, as aluminum oxide.

The stranded conductors are also transnovelty which characterize my invention will posed in a suitable manner, such as that illustrated, wherein the conductors are twisted with respect to the longitudinal axis of the stud, so that the eddy current effect of alternating currents is materially reduced. The manner of transposing the conductors to roduce this result may obviously vary since stranded conductors of this type are Well known.

For the purpose of eliminating heatin at to the union between the conductor stud an its terminal members, solid terminal members are integrally united, as by brazing or cold pressing, to the individual conductors at opposite ends of the stud so as to form a uni- 66 for-mly conducting part thereof. At one end of the stud a solid conducting member, as a cast copper sleeve 2, is fastened, as by brazing or by cold pressing as at 2, on to the individual conductors 1 so as to form a substan- 7 tially integral part thereof, thereby eliminating high resistance unions between the stud an terminal member as is the case where clamping structures are employed. The terminal member 2 is screw-threaded externally, as at 3, so that it may be suitably connected to an associated conductor.

The stud at its opposite end has united thereto a solid conducting member 4, comprising in the present instance a stationary contact member adapted for fluid-break switching apparatus wherein the contact a is adapted to be engaged by a movable contact 5 within an insulating liquid such as oil. The terminal member 4 ma be of material such as cast copper, and 1s united to the conductors 1 at 1"in the manner above described so as to form a substantially uniform conducting'part thereof. An insulating bushing 6 of suitable character is mount- 99 ed upon the conductor stud and is maintained in position by a nut and washer 7 and 8 coacting with the screw threaded surface 3 of the sleeve 2.

It shall be understood that it is within the scope of my invention to employ any suitable method of integrally uniting the solid terminal members to the individual conductors to form a uniformly conducting part thereof, and to arrange the individual conductors in other ways than herein illustrated for the purpose of reducing the skin eflect of alternating currents and thereby increasing the current carrying capacity of the stud.

5 What I claim as new and desire to secure by Letters Patent of the United. States, is,-

1. An electrical conductor stud comprising a plurality of individually transposed conducting portions, means for insulating said portions from each other, and a solid conductingter'minal member integrally united to each end of said conductor so as to form an integrally uniform conducting union between saidtransposed conducting portions and said terminal members.

2. An electrical conductor studfor carrying comparatively large currents comprising a plurality of stranded conducting portions insulated from each other, said portions being transposed so as to reduce skin efiect of alternating currents traversing said stud, and a solid conducting terminal member integrally united to form a uniformly conducting part at each end of said stud.

I Y 3'. In electrical switching apparatus of large current carrying capacity, an electrical conductor stud comprising a plurality of transposed conductors so arranged as to provide approximately equal reactance circuits through said stud,said transposed portions being insulated from each other, a conducting sleeve forming one terminal of said stud and integrally united thereto to form a solid uniformly conducting union, and a solid conducting hlock forming a contact of said switching apparatus integrally united to the opposite end of said stud to form therewith a solid uniform conducting portion.

4. In electrical fluid-break switching apparatus for carrying comparatively large alternating currents, an electrical conductor stud associated with the contact structure of the switching apparatus comprising a plue5 rality of stranded conductors transposed so as to increase the current carrying capacity ofisaid stud, said conductors being insulated from each other, a cast conducting sleeve having a brazed union with one end of said stud to form a terminal thereof, and a cast block having a brazed union With the opposite end of said stud to forma stationary contact of said switching apparatus.

5. A method of making an electrical conductor stud which comprises transposing a plurality of individual conductors so as to provide low erdective resistance to alternatmg currentsto form a main current carrying portion, and brazing a solid conducting 60 member to each end of the stud.

6, A. method of making an electrical conductor stud adapted to carry comparatively large currents, which comprises transosing a plurality of stranded conductors, Q5 hrazing a cast terminal member to one end of said stud to form an integral uniform conducting union with said stranded con-- 

